diff --git a/src/parse.c b/src/parse.c
index 2b89227..bdb94d7 100644
--- a/src/parse.c
+++ b/src/parse.c
@@ -98,6 +98,8 @@ handle_one_option(int opt, char **argv, void *config,
 		return error_invalid_opt(current_opt);
 
 	desc = find_option_handler(opt, opts, nb_opts);
+	if (NULL == desc)
+		return CLI_ERROR;
 	bitmask_index = (size_t)(desc - opts);
 	if (HAS_FLAG(*opt_tracker, (1ULL << bitmask_index)))
 		return error_duplicate_opt(current_opt);